8yrs ago I had a total thyroidectomy due to thyroid cancer since then my dose has gone from 50 to 150 to 125 to 100 to 50 and now back to 100. I'm not sure what is going on but I have never felt the same I'm always extremely tired especially when I was on 50, I couldn't stay awake. My doctor put me on 100 but I'm still very tired no energy and have gained 10 kilos in the last 3 months. I have my test taken every three months and am told I should go back to 50 but I cannot live on 50. I use to feel very energetic when I was on 125 but was told that dose was too high. What can I do. Really fed up. Deslee